FreeBSD and OpenBSD are increasingly gaining traction in educational institutions, non-profits, and corporations worldwide because they provide significant security advantages over Linux. Although a lot can be said for the robustness, clean organization, and stability of the BSD operating systems, security is one of the main reasons system administrators use these two platforms.

There are plenty of books to help you get a FreeBSD or OpenBSD system off the ground, and all of them touch on security to some extent, usually dedicating a chapter to the subject. But, as security is commonly named as the key concern for today`s system administrators, a single chapter on the subject can`t provide the depth of information you need to keep your systems secure.